New to MobileMe | Problems syncing...

I recently took out the 60 day MobileMe trial. I've managed to get email syncing fine but I'm having problems with the rest. Currently I just use iCal on my MacBook or Calendar on my iPhone and when I connect the iPhone to the MacBook they sync. I tried setting it up via MobileMe but I ended up either losing my calendar or having duplicates. I tried syncing contacts too and when I looked in my iPhone ALL of my contacts were gone, I had to restore my iPhone using iTunes. I've been a little too scared to try this again in case I lose things.

Can anyone help me. I thought this would all be a little easier. When I go in MobileMe settings on my MacBook it asks me about merging things etc and it's a little confusing... please help!